The requirements of always higher thermal performances of turbine vanes and blades push all the aeroengine industries to invest in new cooling technologies. AVIO, the italian aerospace propulsion industry, developed during the last three years an innovative cooling systems for stationary components, based on the doublewall technology, that allow to enhance the internal heat exchange optimising the cooling air distribution. The thermal behaviour of the system has been studied numerically using the standard integrated design methodologies. Some components have been then manufactured in real geometries and finally tested at high temperature in the AVIO’s burner rig. Aim of this work is to present the cooling design methodology used, the manufacturing phases, and to compare the measured thermal efficiency with the theoretical ones. The experimental tests of the blade at high temperature burner rig allowed to determine the effectiveness of the cooling system and validate the integrated aero-thermal numerical procedures. Experimental values of effectiveness are reported in relation with the numerical expected data. Therefore a comparison between this new technology and standard ones based on impingements and turbulated channels is taken into account. Overall numerical results have been found in good agreement with the experimental data and indicate that doublewall cooling system can provide heat transfer enhancements and higher thermal performance if compared with conventional cooling methods with potential benefits on cooling reduction and streamwise uniformity in heat transfer coefficients. Further future improvements and developments are here preliminary proposed.

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